Window coverings are made of plastics, cloth, linen, gauze, aluminum sheet, wood chip, metal materials and so on, which have functions of sunshade, heat insulation, and indoor light adjustment. According to the control manners of the window coverings, the window coverings may be generally classified into window coverings with manually operated curtain pull cords and window coverings with electrically operated curtain pull cords. The window coverings with manually operated curtain pull cords further include: manually opened-and-closed window coverings, roller blinds with manually operated pull beaded-chains, manually operated silky hanged window coverings, manually operated window blinds, manually operated Roman blinds, manually operated organ shade and the like. The window coverings with electrically operated curtain pull cord include electrically opened-and-closed window coverings, electrically operated roller blinds, electrically operated silky venetian blinds, electrically operated sky-light blinds, electrically operated window blinds, electrically operated Roman blinds, electrically operated organ shade and the like. With their development, the window coverings have become an indoor decoration in combination with functionality and decorativeness perfectly which are indispensible for households.
In the conventional technology, manually operated window coverings generally control the reeling up or retracting of window covering curtains by manually operated pull cords. In this method, control of the pull cord is required to be manually performed, thus the pull cord is generally arranged at a position with a small height, and is easily touched by a child. If the pull cord winds the neck of the child, the life safety of the child may be threatened. The electrically operated window coverings, though is controlled by motors or other electric apparatus rather than through the operation of the manually operated curtain pull cords, the window coverings of such kind doubtlessly increase a production cost thereof, and also the motors generally need to be periodically maintained, thus needing to pay a certain maintenance cost, for example, adding lubricating oil, etc., and furthermore, for an ordinary user, the detachment and maintenance are troublesome.